Yes, a couple of big signings would have been good, but it's not everything. Last year the Reds were going to blow everyone away with their signings of Moore, Smith, Higginbotham, Tui, Cooper etc, however it didn't happen. Conversely, we all thought the Brumbies were heading for the bottom with all their losses (Pocock, White, To'omua, Liliafano, Tomani etc) but they outperformed all the other Australian teams.
It comes down to coaching, commitment, effort and belief from the players, little things like not giving away too many penalties and kicking your goals, not losing key players to injury and of course, gelling as a team, where the total is better than the sum of the parts. I'm not saying for a minute we'll get that right (certainly didn't last year) but that's what it's all about.
Besides, a roster including Latu, Kepu, Hooper, Dempsey, Foley, Beale and Folau isn't that rough.